Positives: excellent location - about 8 mins' walk to the sky train (equivalent to metro) station; practically part of the station is Sathorn, Bangkok's main pier, from which you have cheap and fast access to all Chao Praya river piers. Also, frequent buses can take you to any part of Bangkok. The room is clean, safe and quiet; air conditioning is good and the wi-fi signal is strong; there is a sliding door with a mosquito net so you can always have fresh air, as well as a small terrace, a boon for smokers. Host Wimonpak was responsive and easily reachable.
Negatives: the room is incredibly small but ok for a single guest spending a couple of days. It definitely isn't a longer-stay place. There was no knife provided and the kitchen sink is on the terrace!
All considered, good value for money.